Over a six-month period, up to 10 Multnomah County prosecutors who usually handle misdemeanor cases were asked to dig into an unsolved Portland homicide.

They read stacks of crime scene reports, pored over transcripts of witness interviews and examined the evidence collected.

Then, they were asked to come up with investigative leads to pursue.

They met about once a month with senior prosecutors, and after about half a year, they shared their ideas with Portland police cold case investigators.

The unusual exercise proved not only valuable as a training exercise for many young prosecutors, but their direction helped Portland cold case investigators obtain a murder indictment this month. David McDonald, 38, faces murder and attempted aggravated murder charges in the 1996 gang-related killing of a 22-year-old man gunned down in Woodlawn Park.

The district attorney's office plans to continue the innovative partnership, and is looking for the next unsolved Portland case to dive into.

Chief Deputy District Attorney Rod Underhill said he was looking for a way to keep the misdemeanor lawyers engaged in their jobs, at a time when there's little money to send staff to outside training and the poor economy has limited promotions.

"I wanted to be creative in finding ways to keep misdemeanor lawyers intrigued," Underhill said. "Lawyers, prosecutors have different lenses we look through. We bring a different perspective, just a fresh set of eyes to a case. Having our office use that case as a training tool also brought benefits to the police."

The unsolved killing of Michael Anthony Yeggins, who was shot multiple times in the chest and back on the evening of July 11, 1996, was among the stack of cold cases. In 2007, gang enforcement Detectives Todd Gradwahl and Pete Simpson were temporarily assigned to unsolved gang cases, and spent the most time on Yeggins' case. They conducted interviews in Oregon, Washington, Arizona and Colorado.

Yeggins was in Woodlawn Park with a 16-year-old girl shortly before 11:30 p.m. Witnesses told police that a car containing four men pulled up on Northeast Dekum Street, near Bellevue Avenue. Two men got out and walked past the couple. The men turned and asked Yeggins his name. When Yeggins told them, one man fired, hitting him several times. The girl, who was from Kent, Wash., was not injured.

Underhill, who works closely with the bureau's cold case unit, knew that enough time had gone by that perhaps relationships had changed and new information might be available. He discussed his idea with Weatheroy and got his prosecutors involved.

Lauren Kemp, a 2009 law school graduate who prosecutes misdemeanor crimes, was among the lawyers pulled in to dissect the unsolved shooting case. Two prosecutors each were assigned different parts of the case. The group met regularly to brief each other on what they had learned and talk about what to do next.

Kemp focused on key witnesses, checked whether they had criminal backgrounds and ties to a potential suspect.

"It was just an exciting experience in being able to be involved in such a large case," Kemp said. "The goal for most misdemeanor deputies is to advance and handle cases like this some day, but that's a long way off when you're starting at the beginning and doing disorderly conduct or harassment cases."

The prosecutors squeezed the work in between their regular caseloads, after hours or on weekends. After meeting at least once a month for six months, they brought in Weatheroy to detail the investigative avenues they identified.

Several unwilling witnesses in 1996 opened up to detectives 15 years later, either because their relationship with the suspect changed or they were facing charges themselves, Weatheroy said.

Gang prosecutor David Hannon got involved when the case got closer to indictment. He said the attorneys who juggle disorderly conduct, harassment or fourth-degree assault prosecutions were enthusiastic about delving into the homicide case. The training exercise was hands-on, unlike a attending a seminar on a topic such as hearsay evidence. "They were enthused to do it, because they don't typically get to see this stuff," he said.

Weatheroy called Underhill's idea innovative.

"It's a win-win situation," Weatheroy said. "It's a way for the DA's office to bring young prosecutors along, as well as give us an additional set of eyes. You can't have too many eyes on these cold cases."